Connection part for an electrochemical cell having a prismatic shape

Abstract

An electrochemical cell includes a container having a bottom and containing an assembly of parallelepipedal plates consisting of one or more positive plates including positive tabs and negative plates including negative tabs, separated by a separator; one or more covers closing an opening of the container; an electrical connection part of a given polarity connecting a tab of the same polarity to a current output terminal of the cell of the same polarity, fixed to a cover; an electrical connection part of opposite polarity connecting a tab of opposite polarity to a current output terminal of opposite polarity, which is fixed to, and electrically insulated from, the cover, the bottom of the container, or a second cover electrically insulated from the first cover; the connection parts each comprising a support plate having a projecting element for connecting a given polarity tab to the current output terminal of corresponding polarity.

1 . An electrochemical cell comprising:
 a) a container comprising a bottom and containing an assembly of parallelepipedal plates consisting of at least one positive plate and of at least one negative plate separated by a separator, said at least one positive plate comprising a positive tab consisting of a portion of a first current collector not covered with positive active material, said at least one negative plate comprising a negative tab consisting of a portion of a second current collector not covered with negative active material;   b) at least one cover closing an opening of the container;   c) an electrical connection part of a given polarity connecting at least one tab of the same polarity to a current output terminal of the cell of the same polarity, fixed to a cover;   an electrical connection part of opposite polarity connecting at least one tab of opposite polarity to a current output terminal of the cell of opposite polarity, the current output terminal of opposite polarity being fixed either to, and electrically insulated from, the cover, or to the bottom of the container, or to a second cover electrically insulated from the first cover;   the electrical connection part of given polarity and the electrical connection part of opposite polarity each comprising a support plate having one or more connection means, each connection means connecting a given polarity tab to the current output terminal of corresponding polarity.   
     
     
         2 . The electrochemical cell according to  claim 1 , wherein the positive electrical connection part and the negative electrical connection part are fixed on a face of the at least one cover facing the inside of the cell, the negative electrical connection part being electrically insulated from the cover. 
     
     
         3 . The electrochemical cell according to  claim 1 , wherein a weld bead connects a positive or negative tab to a connection means of the connection part of corresponding polarity, the weld bead extending in a direction parallel to the longitudinal plane of the plate. 
     
     
         4 . The electrochemical cell according to  claim 1 , wherein each connection means is a projecting element formed on a face of the support plate oriented towards the inside of the cell. 
     
     
         5 . The electrochemical cell according to  claim 4 , wherein the projecting element has the shape of a triangular prism, one of the faces of the prism serving as a connection surface for connecting one or more tabs to the connection part. 
     
     
         6 . The electrochemical cell according to  claim 1 , wherein the plurality of connecting means forms a series of triangular prisms aligned parallel to one another. 
     
     
         7 . The electrochemical cell according to  claim 5 , in which the an angle of an apex of the prism opposite to the side of the prism in contact with the support plate ranges from 10 to 45°, preferably from 25 to 35°. 
     
     
         8 . The electrochemical cell according to  claim 4 , wherein a height of the projecting element ranges from 2 to 5 mm, preferably from 3 to 4 mm. 
     
     
         9 . The electrochemical cell according to  claim 1 , wherein a height of the tab ranges from 3 to 10 mm, preferably from 4 to 7 mm, more preferably from 5 to 6 mm. 
     
     
         10 . The electrochemical cell according to  claim 1 , of the lithium-ion type. 
     
     
         11 . A method of manufacturing an electrochemical cell comprising the steps of:
 a) providing at least one cover;   b) fixing a first electrical connection part of a given polarity on one face of said at least one cover, said face being intended to be oriented towards the inside of the cell, and fixing a second connection part of opposite polarity either on the a same face of the cover, with the second connection part being electrically insulated from the cover, or on a face of a second cover, said face being intended to be oriented towards the inside of the cell, the two electrical connection parts each comprising a support plate having one or more connection means;   c) providing a plate of given polarity, said plate comprising a tab consisting of a portion of a first current collector not covered with active material;   d) welding the tab of step c) to a connection means of the connecting part of corresponding polarity;   e) placing a separator on the plate obtained in step d);   f) providing a plate of opposite polarity to that of the plate of step c), said plate comprising a tab consisting of a portion of a second current collector not covered with active material;   g) welding the tab of step f) to a connection means of the connection part of corresponding polarity;   h) repeating steps c) to g) to obtain an electrochemical plate group.   
     
     
         12 . The method according to  claim 11 , further comprising the step i) of inserting the electrochemical plate group connected to said at least one cover into a container of parallelepipedal format. 
     
     
         13 . A method of manufacturing an electrochemical cell comprising the steps of:
 a) providing at least one cover and a parallelepiped format container, at least one of the walls of the container being constituted by the incorporation of said at least one cover;   b) fixing a first electrical connection part of a given polarity on a face of the cover, said face being intended to be oriented towards the inside of the cell and fixing a second electrical connection part of opposite polarity either on the same face of the cover, the second electrical connection part being electrically insulated from the cover, or on a wall of the container other than the cover, or on a face of a second cover, said face being intended to be oriented towards the inside of the cell, the two electrical connection parts each including a support plate having one or more connection means;   c) placing a plate of given polarity adjacent one of the two walls of larger surface of the container, said plate comprising a tab consisting of a portion of a first current collector not covered with active material;   d) welding the tab of step c) to a connection means of the connection part of corresponding polarity;   e) placing a separator on the plate obtained in step d);   f) placing on the separator a plate of opposite polarity to that of the plate of step c), said plate comprising a tab consisting of a portion of a second current collector not covered with active material,   g) welding the tab of step f) to a connection means of the connecting part of corresponding polarity;   h) repeating steps c) to g) to obtain an electrochemical plate group.   
     
     
         14 . The method according to  claim 11 , wherein the welding of the tab of steps d) and g) is performed in a direction parallel to the longitudinal plane of the plate. 
     
     
         15 . The method according to  claim 11 , in which the welding of steps d) and g) is carried out using a laser, the beam of which forms an angle of 10 to 45° with respect to the a longitudinal plane of the cover, preferably ranging from 25 to 35°. 
     
     
         16 . The method according to  claim 12 , in which the welding of steps d) and g) is carried out using a laser, the beam of which forms an angle of 10 to 45° with respect to a longitudinal plane of the cover, preferably ranging from 25 to 35°. 
     
     
         17 . The method according to  claim 13 , in which the welding of steps d) and g) is carried out using a laser, the beam of which forms an angle of 10 to 45° with respect to a longitudinal plane of the cover, preferably ranging from 25to 35°. 
     
     
         18 . The method according to  claim 12 , wherein the welding of the tab of steps d) and g) is performed in a direction parallel to the longitudinal plane of the plate. 
     
     
         19 . The method according to  claim 13 , wherein the welding of the tab of steps d) and g) is performed in a direction parallel to the longitudinal plane of the plate. 
     
     
         20 . The electrochemical cell according to  claim 6 , in which an angle of an apex of the prism opposite to the side of the prism in contact with the support plate ranges from 10 to 45°,preferably from 25 to 35.